2004 SUBARU FORESTER engine

EN(H4DOTC 2.5)-213
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK ANY OTHER DTC ON DISPLAY.Is any other DTC displayed? Inspect the rele-
vant DTC using
“List of Diagnostic
Trouble Code
(DTC)”. EN(H4DOTC 2.5)-
65, List of Diag-
nostic Trouble
Code (DTC).>
N
OTE:
In this case, it is
not necessary to
inspect DTC
P1544.Go to step 2.
2 CHECK EXHAUST SYSTEM.
Check exhaust system parts.
NOTE:
Check the following items:
 Loose installation of exhaust manifold
 Cracks or hole of exhaust manifold
 Loose installation of front oxygen (A/F) sen-
sorIs there a fault in exhaust sys-
tem?Repair or replace
failure, then
replace the precat-
alytic converter.Contact the SUB-
ARU dealer.
NOTE:
Inspection by DTM
is required, because
probable cause is
deterioration of mul-
tiple parts.

EN(H4DOTC 2.5)-214
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BS:DTC P1560 BACK-UP VOLTAGE CIRCUIT MALFUNCTION
DTC DETECTING CONDITION:
Immediately at fault recognition
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02356
B72
B135
3412
BATTERY MAIN RELAY
SBF-4 SBF-1SBF-5
B72
D16 D7
B12
A6
A7
B1
B4
D1
D2
A34B5
B6
B19
D14
No.11
B47
E2 B21 1 2 3 5 6 4
ECM
E
E
1 4
B134
B135
B137 A:
B:
D:
14133
15
16
34 12
56123
4
56
78
91011 12
1314 15 16
B134 B21 B47B137 A: D:
B: IGNITION
SWITCH
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
567
82 1
94 310
24 22 23 2511 12 13 14 15
26 27
2816 17 18 19
20 21
29 30 31 32 33 34 35
567
82 1
94 310
22 23 11 12 13 14 15
24 25
2616 17
18 19 20 21
27 28 29 30 31

EN(H4DOTC 2.5)-215
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK INPUT SIGNAL FROM ECM.
1) Turn the ignition switch to OFF.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B135) No. 19 (+) — Chassis ground (
−):Is the voltage more than 10 V? Repair the poor
contact in ECM
connector.Go to step 2.
2 CHECK HARNESS BETWEEN ECM AND
MAIN FUSE BOX CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and chassis ground.
Connector & terminal
(B135) No. 19 — Chassis ground:Is the resistance less than 10
Ω?Repair ground
short circuit in har-
ness between ECM
connector and bat-
tery terminal.Go to step 3.
3 CHECK FUSE SBF-5.Is the fuse blown out? Replace the fuse. Repair the harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ECM and battery
 Poor contact in
ECM connector.
 Poor contact in
battery terminal

EN(H4DOTC 2.5)-216
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BT:DTC P2088 OCV SOLENOID VALVE SIGNAL A CIRCUIT OPEN (BANK 1)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02375
B22
E3
B134
E38
28 2 1
2
1
E38
B22
12
18
125678
131415169101112
34
17181920
B134
56 7
82 1
94 3
10
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
ECM
OIL FLOW CONTROL SOLENOID VALVE RH

EN(H4DOTC 2.5)-217
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B134) No. 18 — (E38) No. 1:
(B134) No. 28 — (E38) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness between
ECM and oil flow
control solenoid
valve connector.
N
OTE:
In this case, repair
the following
 Open circuit in
harness between
ECM and oil flow
control solenoid
valve connector
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
Measure the resistance between oil flow con-
trol solenoid valve and engine ground.
Connector & terminal
(E38) No. 1 — Engine ground:
(E38) No. 2 — Engine ground:Is the resistance more than 1
MΩ?Go to step 3.Repair short circuit
between ECM and
oil flow control
solenoid valve
connector.
3 CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 6 — 12 Ω? Repair poor con-
tact in ECM and oil
flow control sole-
noid valve.Replace the oil
flow control sole-
noid valve. to ME(H4DOTC)-
68, Camshaft.>

EN(H4DOTC 2.5)-218
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BU:DTC P2089 OCV SOLENOID VALVE SIGNAL A CIRCUIT SHORT (BANK 1)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02375
B22
E3
B134
E38
28 2 1
2
1
E38
B22
12
18
125678
131415169101112
34
17181920
B134
56 7
82 1
94 3
10
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
ECM
OIL FLOW CONTROL SOLENOID VALVE RH

EN(H4DOTC 2.5)-219
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B134) No. 18 — (E38) No. 1:
(B134) No. 28 — (E38) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness between
ECM and oil flow
control solenoid
valve connector.
N
OTE:
In this case, repair
the following
 Open circuit in
harness between
ECM and oil flow
control solenoid
valve connector
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between oil flow
control solenoid valve and engine ground.
Connector & terminal
(E38) No. 1 — Engine ground:
(E38) No. 2 — Engine ground:Is the resistance more than 1
MΩ?Go to step 3.Repair short circuit
between ECM and
oil flow control
solenoid valve
connector.
3 CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 6 — 12 Ω? Repair poor con-
tact in ECM and oil
flow control sole-
noid valve.Replace the oil flow
control solenoid
valve. ME(H4DOTC)-68,
Camshaft.>

EN(H4DOTC 2.5)-220
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BV:DTC P2092 OCV SOLENOID VALVE SIGNAL A CIRCUIT OPEN (BANK 2)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02376
B22
E3
B134
E37 ECM
29 2 1
4
3
19
OIL FLOW CONTROL SOLENOID VALVE LH
E37
B22
12
125678
131415169101112
34
17181920
B134
56 7
82 1
94 3
10
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31